Sound reproducing or recording machine.



"9111f; UNDERHIL LI SOUND' REPRODUCING 0R RECORD-ING MACHINE.

; APPLICATION r1150 MAY 21. 1905. 7 1 ,141,672.

Pafnted June 1, 19.15.

five 211502 660255121X H. UNDEBHILL, 0F BOSTON, MASSACHUSETTS,

SOUND REPBQDUCIXG 0R RECORDING MACHINE.

Specification of Letters Patent.

Patented June 1, 1915.

(Jriginal application filed June 11, 1904, Serial No. 212,079. Divided and this application filed May 27,

To (ZZZ c071 om it may concern Beit known that I, Grouse H. UNDER- HILL, a citizen of the United States, and resident of Boston, in the county of Suffolk and State of ldassachusetts, have invented an Improvement in Sound Reproducing or Recording Machines, of which the following description, in connection with the ac co'mpanying drawings, is a specification, like letters on the drawings representing like parts.

My invention relates to phonographic apparatus, being more particularly concerned with improvements in the sound reproducing and sound recording mechanism thereof.

The present application is a divisional of my prior copending application, Serial Number 212,079, filed June 11, 190%.

My invention will be best understood by reference to the following description, when taken in connection with the accompanying illustration of one specific embodiment thereof selected for illustrative purposes only; while its scope will be more particularly pointed out in the appended claims. r

In the drawings-Figure 1 is a plan showing one form of sound box constructed according to my invention; Fig. 2 is a front elevation thereof, partially broken away; Fig. 3 is a section on the line 3-3, Fig. 2; Fig. l is a view looking from beneath the sound box as seen in Fig. 2: Fig. 5 is a section on the line 5-5, in Fig. 4; Fig. 6 shows one form oft-he removable throat; and, Fig. 7 is a different form thereof.

Referring to the drawings I have there shown one form of my improved sound box, the same together with its associated parts being shown without reference to any particular phonographic machine. The sound box there shown is applicable to various types of commercial machines, and its adaptation and application thereto, so far as it is not referred to in the following description, will be obvious to those skilled in the art.

The sound tube, a, is preferably bifurcated, to provide the branches, j, and, 70, into which may he slid and frictionally held the tubular portions, j, and. k, of the sound box. The latter is provided with a double set of recording and reproducing devices,

and I have herein shown those of. one set Serial No. 262,579.

as substantially duplicated by those of the other set. This, it is to be understood however, is not essential to my invention as the diaphragm and other elements of the mechanism may for certain purposes be widely diflerent. The sound box consists generally ofa double head or casing, z", and when in use is adapted to be frictionally held within a suitably shaped double yoke, secured to a movable arm, by which the sound box will be caused to traverse the record.

The casing, i, is provided with two cylindrical portions, i and i that shown in, 2', for example (see Fig. 5), being provided with a diaphragm, F, placed between two annular rings of yieldable packing material, such as rubber, and held against a shoulder in the casing by means of the back-piece, is, screwed into the back of the casing 2" against the preferably metallic washer, is. WVithin the tubular portion, A of the back-piece, h and preferably axially alined therewith and with the diaphragm, it, I have provided the throat. 72 preferably threaded or otherwise constructed to provide adjustment thereof relatively to the face of the diaphragm, the I end of the throat adjacent the diaphragm being suitably shaped for the most efficient effect, as by beveling the same. in the man ner shown.

I have found that it is not only desirable to have the sound orifice of each throat adjustable relatively to the diaphragm, but that each particular class of sound requires a special sound orifice for its most effective reproduction. For e. ample I have found that the full harmony of a brass band will usually be best dcvrloprd through the employment of a throat having the general form of that shown in l igs. 5 and (3. while the note of a violin is more faithfully reproduced by a differently shaped throat, as, for example, that shown in section in Fig. 7. This I believe to be due to a capacity of the throat shown in Fig. 7, where its formation is relatively sharp, for selecting to a greater extent those waves emanating from the center of the diaphragm, and the caacity of the throat shown in Fig. 5, which is comparatively blunt for receiving and transmitting to a greater extent sound vibrations acting not only from the center but from the extremities of the diaphragm as well. The provision of means for altering the character of the passage for sound waves to or from the diaphragm, such, for example, as by providing a plurality of such throats, -each proportioned or formed with respect to a particular quality of sound, in the reproduction of which it is intended to be used, and replaceable one by another, forms an important feature of my invention. Referring to Figs. 5 and 6, I have provided the slot, is", in the outer end of the throat member, which, when the box is removed from the sound tube, may be conveniently engaged by a screw driver or other implement to adjust the mouth of the throat in any desired relative position to the diaphragm, or to remove the same entirely and replace it by another of difl'erent shape, s ze or proportion.

The two styli are here employed in order to provide a multiple effect; the production of which, however, is v: dbviously not limited to the use merely of two' Each of two styli, Z, and, m, is connected'to its respective diaphragm through the connecting body, Z, m, the links Z", and, m", and the rockshafts, Z m so that, when in the operative position shown in Fig. 2 (see also Fig. 4), the point of the'second stylus is caused to trail in the same record groove as the first stylus, but directly and immediately behind the latter, and also arranged so that the vibrations communicated to each stylus point are transmitted directly and eflieiently to the corresponding diaphragm. The stylus points with their rockshafts are respectively supported and movable with the vibratable levers, Z and m, arranged side by side and hinged at, n (Figs. 3 and 5) topermit the individual and relative movement of the said levers to and from the surface of the record. Additionally the stud 0 carrying the support n is mounted to turn in its seat so as to permit a slight lateral movement common to each stylus movement when such movement is requisite. Thus, although free vibration is ermitted the stylus points in the reproduction of the intended sound, they are compelled always to track one after the other, and the lateral movement of one no matter from what cause,

must be followed by a like movement of the other.

An equalized tension, tending normally to press the stylus points toward the face of the record, is maintained upon-the two stylus points by means of the lever, p, fulcrumed at, 77, carrying the adjustable weight, 79 the latter acting through the bar p, equalizing rod, 7)", and pressure points, 39 p", engaging respectively or connected with the backs of the levers, Z and, m. Thus, when the sound box is adjusted relatively tothe record, and the stylus point or points have found and entered the groove therein, the force pressing the same into the groove may be varied by adjustment of the weight,

along the lever p, this force, however, being distributed upon the two points by means of the equalizing bar, p; thereby to maintain an individual tension upon each of'the cooperating stylus points, such tension being proportioned to their individual requirements and the movement of one stylus point with its supporting lever in no way conflicting with simultaneous movement of the other point and its lever, whether such movements are similar or dissimilar. In order to relieve the diaphragm and its connections from the weight of the stylus parts, including the weight, 30 when the sound box has been lifted or withdrawn from the facerof the record, I have provided the supporting ever, that the points will meet the record at exactly the same spot from which they were withdrawn, the record and the sound box, meanwhile, having undergone no relative movement.

I have found that the arrangement shown of multiple diaphragms, where they are grouped or clustered about a common position toward which their vibration mechanism is directed, provides a highly efiicient, and in fact so far as I am aware the only practical, construction for obtaining a multiple effect. I have also found that the effectiveness of the machine is greatly increased by the inter-connection which exists between the vibration parts of each system through which there is maintained a constant tendency for the stylus points and diaphragms to move in conjunction and cooperation,-each one with the other or others. It will be understood that my invention is susceptible of embodiment in a great variety of forms and may be combined in various ways which I have not here attempted to the scope of my invention as set forth.

I claim- 1. In an apparatus of the class described, a plurality of coeperating stylus points, tension means for said points and means for equalizing the tension.

2. In an apparatus of the class described the combination with a plurality of stylus points arranged to cooperate onel' with the other in substantially the same portion of the same record groove, connecting means illustrate, since the same are included within v between the same and movable therewith, on means for said a plurality of diaphragms connected respectively with said points, each of said diaphragms having a separate chamber.

3. In an apparatus of the class described the combination with aplurality of stylus points arranged to cooperate one with the other in substantially the same portion of the same record groove, ot a plurality of diaphragms laterally disposed with respect to the record groove and connected with said points.

at. In an apparatus of the class described, the combination with a plurality of diaphragms having their respective sound boxes grouped with reference to substantially the same point of stylus action, of vibratory mechanism for each of said diaphragms in cluding independent stylus points and stylus connections diverging generally from such point of stylus action.

5. In a sound-reproducing or sound-recording macfhine the combination with a plurality of cooperating diaphragms, of cooperating and inter-connected stylus points for said diaphragms.

6. In a sound-reproducing or sound-recording machine the combination with a plurality of sound boxes, provided each with its diaphragm, of a plurality of cooperating and inter-connected stylus points for said diaphragms. V

7 In anapparatus of the class described the combination with a. plurality of cooperatively arranged stylus points, of means a for permitting independent reproducing i bratory movement of said points, and means for providing individual tension therefor including connecting means between said points and movable therewith.

S. In an apparatus of the class described a plurality of. cooperating but independently vibratory stylus points and common tensioning means for said points.

9. In an apparatus of the class described, a plurality of cooperating stylus points and common equalizing tension means for said points.

10. In an apparatus of the class described a plurality of cooperating but independently vibratory stylus points, of tension points having a common ad gustinent.

11. In an apparatus of the class described a plurality of cooperating stylus points, of

equal 2mg tension means for said points havirg a common adjustment.

12. 'In an apparatus of the class described the ccmbination with a plurality of cooperating diaphragms of cooperating stylus points connected respectively to said diaphragms, said stylus points'being carried by pivoted members having a common axis. 13. In an apparatus of the class described a plurality of stylus points carried respectively by members having independent vibratory movement, said members being arranged side by side to tive movement.

14. In an apparatus of the class described a plurality of stylus points pivoted for independent movement in one plane but having a common pivotal axis for like movement in another plane.

15. In an apparatus of the class described a plurality of stylus supporting levers pivoted for independent movement and a 001m mon carrying member to which said levers are attached, said carrying member being also pivotally mounted to permit likemovement of said stylus levers in one direction.

16. In an apparatus of the class described, the combination with vibratively separate stylus levers adapted to respond in unison to substantially the same portion of the sound groove, common tensioning means for said stylus levers, means whereby the common but separated lever vibrations are conprevent lateral relaverted into air vibrations and again united,

GEORGE H. UNDERHILL. I

lVitnesses Trroams B. Boo'ra, Ewsnn'r'r S. Emma. 

